Conventional printed circuit boards (PCBs) include electrically insulative layers and electrically conductive layers alternatingly arranged along the thickness of the printed circuit board. Certain ones of the electrically conductive layers are typically configured as signal layers, and certain others of the electrically conductive layers are typically configured as ground layers. The signal layers each can include electrical signal traces that are supported and surrounded by electrically insulative material, and the ground layers can include one or more electrically conductive regions that are supported and surrounded by electrically insulative material. Because the ground layers are disposed between adjacent signal layers, the ground layers provide shielding between the electrical signal traces of one signal layer and the electrical signal traces of the adjacent signal layer. Conventional printed circuit boards can include at least first and second linear arrays that each contain signal vias and ground vias. The ground vias extend through at least one of the signal layers and are placed in electrical communication with the electrically conductive region of a respective one of the at least one ground layer. The signal vias can be arranged in first and second differential signal pairs that are placed in electrical communication with respective first and second sets of electrical differential signal traces that route electrical signals along the printed circuit board. The first linear array includes the signal vias of the first differential signal pair, and the second linear array includes the signal vias of the second differential signal pair. Each of the first and second linear array can include a respective at least one ground via. The electrical signal traces are positioned between the first and second linear arrays, and are oriented parallel to the linear arrays. The electrical differential signal traces are positioned so as to be symmetrical about a center line that extends equidistantly between the first and second linear arrays. In certain implementations, conventional printed circuit boards further include first and second arrays of ground vias that are disposed between the respective first and second linear arrays and the electrical signal traces.